Means for guiding the workpiece in sharpening machines



Mmm/4,1936. STEINER 2,035,249

MEANS FOR GUIDING THE WORKPIECE IN SHARPENING MACHINES Filed NOV. 25, 1952 i 66 ,a4 afa/fa@ Patented Mar. 24, 1936 UNITED STATES PATENT OFFICE MEANS FOR GUIDING THE WORKPIECE IN SHARPENING MACHINES Leo Steiner, Budapest, Hungary 3 Claims.

My invention relates to improved means for guiding the work piece in that type of sharpening machines in which both sides of a cutting edge of the work piece are simultaneously operated on between a pair of rotating sharpening cylinders while the work piece travels longitudinally o-f said cylinders between a pair of guide rails which prevent it from tilting an any other lateral displacement but leave it full freedom of movement in the vertical plane passing through the edge to be sharpened. Such machines are described and claimed in my Patent No. 1,941,501 issued January 2, 1934. The chief objects of the invention are to substitute rolling friction for sliding or rubbing friction on said guide rails, and to change the normally rolling friction to sliding or rubbing friction atv such longitudinal sections of said guide rails where retarding of the progress of the work piece is desired. Other objects of the invention will appear from the following description of an embodiment of the invention illustrated by way of example in the accompanying drawing in which- Fig. 1 is a diagrammatic side View of a sharpening machine provided with the improved means of the invention for guiding flexible razor blades between helically grooved and interengaging sharpening cylinders; only one ofthe pair of cylinders appears in this figure, the other being located behind and therefore masked by the same. Fig. 2 is a top view, on larger scale, of a longitudinal portion of the improved guiding means. Fig. 3 is a section on line 3-3 of Fig. 2, showing also the interengaging cylinders 35 in cross section. Fig. 4 is a part longitudinal section on line 4-4 of Fig. 3.

In the sharpening machine diagrammatically shown in Fig. l, two uprights 5 and 6 are secured by bolts I upon opposite ends of a baseplate 8. The sharpening cylinders 9 and IIJ rotatably mounted in the uprights 5 and 6 have helically grooved surfaces, the grooves of one cylinder being of right-hand turn and those of the other cylinder being of left-hand turn. The grooves and the corresponding helical projections of the two cylinders are in mutual engagement so that a wedge-shaped sharpening path with curved walls is formed between the interengaging cylinders as clearly shown in Fig. 50 3. The bearings for the cylinders are at a higher level in one of the uprights than in the other so that the longitudinal axes of the cylinders as well as the sharpening path between the cylinders are sloping i. e. form an angle with the horizontal. Any driving means (not shown) may be provided to impart to the cylinders 9 and I0 rotation in opposite directions, as indicated by arrows in Fig. 3, the rotation of each cylinder being directed against the edge of the blade II to be sharpened.

Secured to the top portions of the uprights 5 and 6 are a pair of guide rails I2, I3 which extend parallel to each other from lthe higher situated feed end to, and beyond, the lower situated delivery end of the cylinders 9 and II) and have throughout their length plain confronting sides l4,- I5 in Vertical planes parallel to the cylinder axes.

The work pieces, supposed to be double-edged exible razor blades in the case illustrated in the drawing, are secured in holders which coperate with the guide rails I2, I3 to prevent the work pieces from tilting and any other lateral displacement without interfering with their full freedom of movement within a vertical plane parallel to the confronting sides I4 .and I5 of the guide rails. Each of these, holders has a body portion I6 fitting between the confronting sides I4 and I5 of the guide rails without coming in contact with them. In this body portion I6, a roller I'I having an outer diameter very slightly smaller than the space between the confronting side walls I4 and I5 is so mounted as to roll upon one or the other of the walls I4 and I5 when the holder travels along the sharpening path between the cylinders 9 and I0. In the drawing, the difference between the diameter of roller II and the space between the walls I4 and l5 is much exaggerated for the sake of clearness.

Each holder body I6 is provided at its lower end with a pair of Wings I8 and I9 forming a clamp for the Work piece II. Wing I8 is integral with the holder body I6, and wing I9 is hinged at 20 so as to allow it to open the clamp which is normally held closed by a spring 22. Two pegs 23 projecting from the inner side of wing I8 and passing through the usual blade holes and through corresponding holes in the wing I9 secure the blade when clamped in between the wings in position. This clamping device, however, does not form part of my present invention.

In Figs. 1 and 2 there is also shown a device for retarding the progress of the work pieces during their travel along the sharpening path formed between the cylinders 9 and I0. The guide rail I2 has a longitudinal slot 24 through which a flat spring 25 fixed upon rail I2 at 26 so projects as to abut with a certain pressure against one side of the periphery of the roller II when the opposite side is in contact with the other guide rail I3. Rotation of the roller I1 is thus prohibited so that the normally rolling friction of roller I`I is changed to a sliding or rubbing friction which retards the progress not only of that holder whose roller I'I is in contact with spring but also of a number of subsequent holders which .have not yet reached the spring 25 but are withheld by the holder whose roller is in contact with spring 25. 'I'his retarding action may be regulated by varying the pressure of spring 25 against roller I'I b y means of a set-screw 2'I. Although I have shown one retarding device only, it will be understood that a number of such devices may be provided for, if desired, at different longitudinal :sections of the guide rails I2 and I3.

That portion of the rails I2 and I3 which extends beyond the delivery end of the pair of cylinders 9 and IU is provided with acclivitous top surfaces 28, for coperation with a pair of projections 29 extending from opposite sides of the holder bodies I E above the rails I2 and I3. In the constructional form shown by way of example in the drawing, these projections 29 carry rotatable rollers 30 adapted to roll upon the to-p surfaces of the guide rails I2 and I3 but situated at such a height as will exclude any contact with the rails as long as the blade clamped in the holder is operated on between the cylinders 9 and ID. However, as soon as a holder in its progress along the cylinders reaches the delivery end of the latter, its rollers 3E) will engage upon the acclivitous top surfaces 28 of the rails to ensure correct removal of the finishedblade from between the cylinders. As the holders when they are raised by hand from between the cylinders are further guided between the vertical confronting sides I4 and I5 of the guide rails, lateral deviations involving damage to the fine cutting edge are avoided.

It should be understood that the word sharpening as used in the description and the claims is to be understood as including grinding, honing, burnishing, polishing and stropping.

I am aware of a blade-sharpening device shown in Patent No. 1,771,171, to George Fortune, and 4in which a roller is vcentrally and obliquely mounted in the blade-holder for supporting the holder at an inclination upon a stropping or honing surface, and I do not claim a blade-holder with a centrally mounted `roller in general but what I claim is:-

l. Improved means for guiding the work piece in sharpening machines of the class referred to, comprising a pair of grooved interlocking rotatable sharpening cylinders forming at the intersection of their surfaces a sharpening path wedge-shaped in cross section; a pair of fixed guide rails extending parallel to each other and having plain confronting sides in vertical planes parallel to the axes of said cylin-ders; a workholder having a body portion fitting between said confronting sides without coming in contact with them; a roller vmounted in said body portion on a vertical axis and having an outer diameter very slightly smaller than the distance between said confronting sides so as to roll at one time upon `the one, at another time upon the other,

of said confronting sides, all contact between said work-holder and said guide rails being restricted on the one hand, to the periphery of said roller and on the other hand, to said confronting sides of the guide rails so that the whole of said work-holder is free to glide up and down between said guide rails, its doWn- Ward movement being restricted by the work bearing upon said sharpening path; and a flat spring secured to, and projecting through a longitudinal slotin, one of said guide rails so as to press with adjustable pressure against one side of said roller when the opposite side thereof is in contact with the other of said guide rails.

2. Improved means lfor guiding the work piece in sharpening machines of the class referred to between a pair of sharpening cylinders, comprising a Ypair `of xed guide rails extending parallel to each other and with their confronting sides parallel to the axes of said sharpening cylinders from the feed end Vto and beyond the delivery end of lthe latter and having plain vertical confronting sides throughout their length and acclivitous top surfaces in that portion of their length extending beyond the delivery end of said cylinders, in combination with a work-holder so guided between said confronting sides as to be prevented from tilting and any other lateral displacement ybut to have full freedom of movement within a vertical plane parallel to said confronting sides, and carrying a pair of projections extending above said guide rails at such a height as will exclude their contact with all portions of said guide rails other than said acclivitous top surfaces, but will ensure engagement and cooperation with the latter.

3. Improved .guiding means as claimed in claim .2, having lrollers so mounted on the projections of the work-holder as to avoid contact with all portions 4of the guide rails other than the .acclivitous ltop surfaces and to roll upon the latter.

LEO STEINER. 

